Migrate HBase of an earlier version

Compared with earlier versions, HBase Client 1.0.0 has big changes which are incompatible with HBase Client of earlier versions.

If you use an HBase Client from version 0.x.x (that is, an earlier version than 1.0.0), this topic explains how to integrate your HBase Client version with Table Store.

Connection APIs

HBase 1.0.0 and later versions cancel the HConnection APIs, and instead use the org.apache.hadoop.hbase.client.ConnectionFactory series to provide the Connection APIs and replace ConnectionManager and HConnectionManager with ConnectionFactory.

Creating a Connection API has relatively high cost, however, Connection APIs guarantee thread safety. When using a Connection API, you can generate only one Connection object in the program. Multiple threads can then share this object.

You also need to manage the Connection lifecycle, and close it after use.

The Table, BufferedMutator, and RegionLocator APIs do not guarantee thread safety. However, they are lightweight and can be used to create an object for each thread.

Admin APIs

From HBase Client v1.0.0, HBaseAdmin APIs are replaced by org.apache.hadoop.hbase.client.Admin. As Table Store is a cloud service, and most operation and maintenance APIs are automatically processed, most Admin APIs are not supported. For more information, see Differences between Table Store and HBase.